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1.
Phys Rev Lett ; 131(15): 150401, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897760

RESUMO

Using a recently developed extension of the time-dependent variational principle for matrix product states, we evaluate the dynamics of 2D power-law interacting XXZ models, implementable in a variety of state-of-the-art experimental platforms. We compute the spin squeezing as a measure of correlations in the system, and compare to semiclassical phase-space calculations utilizing the discrete truncated Wigner approximation (DTWA). We find the latter efficiently and accurately captures the scaling of entanglement with system size in these systems, despite the comparatively resource-intensive tensor network representation of the dynamics. We also compare the steady-state behavior of DTWA to thermal ensemble calculations with tensor networks. Our results open a way to benchmark dynamical calculations for two-dimensional quantum systems, and allow us to rigorously validate recent predictions for the generation of scalable entangled resources for metrology in these systems.

2.
Sci Total Environ ; 903: 166580, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37633387

RESUMO

The facilitation of microplastics (MPs) on bacterial resistance has attracted wide concern, due to the widespread presence of MPs in environmental media and their ubiquitous contact with bacteria strains. Furthermore, MPs possibly co-exist with antibiotics to trigger combined stress on bacterial survival. Therefore, it is significant to reveal the dose-responses of MPs and MP-antibiotic mixtures on bacterial endogenous and exogenous resistance. In this study, 0.1 and 5 µm polystyrenes with no surface functionalization (PS-NF, no charge), surface functionalized with amino groups (PS-NH2, positive charge) and carboxyl groups (PS-COOH, negative charge) were selected as the test MPs, and norfloxacin (NOR) was set as the representative of antibiotics. It was found that six types of PS all inhibited the growth of Escherichia coli (E. coli) but induced hormetic dose-responses on the mutation frequency (MF) and conjugative transfer frequency (CTF) of RP4 plasmid in E. coli. Moreover, these hormetic effects exhibited size- and surface charge-dependent features, where 0.1 µm PS-NH2 (100 mg/L) triggered the maximum stimulatory rates on MF (363.63 %) and CTF (74.80 %). The hormetic phenomena of MF and CTF were also observed in the treatments of PS-NOR mixtures, which varied with the particle size and surface charge of PS. In addition, the interactive effects between PS and NOR indicated that the co-existence of PS and NOR might trigger greater resistance risk than the single pollutants. Mechanistic exploration demonstrated that the increase of cellular reactive oxygen species and the variation of cell membrane permeability participated in the hormetic effects of PS and PS-NOR mixtures on bacterial resistance. This study provides new insights into the individual effects of MPs and the combined effects of MP-antibiotic mixtures on bacterial resistance, which will promote the development of environmental risk assessment of MPs from the perspective of bacterial resistance.

3.
Phys Rev Lett ; 131(3): 036505, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37540853

RESUMO

New or enlarged symmetries can emerge at the low-energy spectrum of a Hamiltonian that does not possess the symmetries, if the symmetry breaking terms in the Hamiltonian are irrelevant under the renormalization group flow. We propose a tensor network based algorithm to numerically extract lattice operator approximation of the emergent conserved currents from the ground state of any quantum spin chains, without the necessity to have prior knowledge about its low-energy effective field theory. Our results for the spin-1/2 J-Q Heisenberg chain and a one-dimensional version of the deconfined quantum critical points demonstrate the power of our method to obtain the emergent lattice Kac-Moody generators. It can also be viewed as a way to find the local integrals of motion of an integrable model and the local parent Hamiltonian of a critical gapless ground state.

4.
Sci Total Environ ; 861: 160574, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36455746

RESUMO

The judgment of joint resistance action is significant for evaluating the resistance risk of antibacterial mixture. Using bacterial mutation frequency (MF) and conjugative transfer frequency (CTF) to respectively characterize the bacterial endogenous and exogenous resistance, mutation unit and conjugative transfer unit have been proposed to judge the joint resistance action of antibacterial mixture at a certain dose. However, these methods could not evaluate the antibacterial mixture's joint resistance action at a larger concentration-range. In this study, the concentration addition for bacterial resistance (CA-BR) approach was used to judge the joint resistance actions between kanamycin sulfate (KAN) and some other typical antibacterial agents, including sulfonamides (SAs), sulfonamide potentiators (SAPs), and silver antibacterial compounds (SACs). Through comparing the hormetic dose-response curves of the binary mixtures on the MF (or CTF) in Escherichia coli (E. coli) and the corresponding CA-BR curves calculated from the hormetic dose-responses of the single agents, the joint resistance actions between KAN and other agents were judged to exhibit dose-dependent feature: with the increase of mixture concentration, the joint mutation actions between KAN and SAs (or SAPs) were fixed at synergism, and the joint mutation actions between KAN and SACs varied from antagonism to synergism; the joint conjugative transfer actions between KAN and other agents changed from antagonism to synergism. Mechanistic explanation suggested that the heterogeneous pattern of joint resistance action had a close relationship with the interplays among the agents' modes of action, and meanwhile was significantly influenced by their joint survival pressure on E. coli. This study reveals the dose-dependent feature for the joint resistance action of antibacterial mixture and highlights the importance of exposure concentration, which will benefit clarifying the resistance risk of antibacterial mixture in the environment.


Assuntos
Escherichia coli , Hormese , Antibacterianos/toxicidade , Interações Medicamentosas , Sulfanilamida/farmacologia
5.
Int Immunopharmacol ; 108: 108911, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35729838

RESUMO

Hepatocellular carcinoma (HCC) is a common malignant tumour in China that remains a major challenge to the medical community, and effective treatment is urgently needed. Due to complex tumorigenesis, monotherapy shows poor therapeutic effects, and combined treatment becomes a necessary option. YW002, a CpG ODN-containing sequence, has been proven to enhance antitumor effects in tumour-bearing mouse models. Moreover, as a broad-spectrum antimicrobial drug, nifuroxazide exhibited an anti-HCC effect through activation of p-Stat3. Here, we tested the effect of nifuroxazide on HCC in vitro and then explored the therapeutic effect of combined nifuroxazide and CpG ODN on HCC in vivo. Nifuroxazide inhibited proliferation, induced apoptosis and suppressed migration and invasion in HepG2 cells in vitro. The combination therapy using nifuroxazide and CpG ODN significantly suppressed the growth of tumours in tumour-bearing mice with few side effects and achieved better therapeutic effects on HCC than monotherapy. Moreover, combined nifuroxazide and CpG ODN therapy significantly induced apoptosis, enhanced the infiltration of CD4+ and CD8+ T lymphocytes and macrophages in tumour tissue, and increased the ratio of CD4+ and CD8+ T lymphocytes in the spleens of tumour-bearing mice. The introduction of this combination therapy combining nifuroxazide and CpG ODN provided a new strategy for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nitrofuranos , Adjuvantes Imunológicos/uso terapêutico , Animais , Linfócitos T CD8-Positivos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Hidroxibenzoatos/farmacologia , Hidroxibenzoatos/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Camundongos , Nitrofuranos/uso terapêutico , Oligodesoxirribonucleotídeos/farmacologia
7.
Environ Sci Technol ; 52(7): 4199-4206, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29537832

RESUMO

Metals can pose hazards to marine species and can adversely affect structures and functions of communities of marine species. However, little is known about how structural properties of metal atoms combined with current geographical and climatic conditions affect their toxic potencies. A mathematical model, based on quantitative structure-activity relationships and species sensitivity distributions (QSAR-SSD) was developed by use of acute toxicities of six metals (Cd, Cr, Cu, Hg, Ni, and Zn) to eight marine species and accessory environmental conditions. The model was then used to predict toxicities of 31 metals and metalloids and then to investigate relationships between acute water quality criteria (WQC) and environmental conditions in coastal marine environments. The model was also used to predict WQC in the coastal areas of different countries. Given global climate change, the QSAR-SSD model allows development of WQC for metals that will be protective of marine ecosystems under various conditions related to changes in global climate. This approach could be of enormous benefit in delivering an evidence-based approach to support regulatory decision making in management of metal and metalloids in marine waters.


Assuntos
Metaloides , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Metais , Qualidade da Água
8.
Yi Chuan ; 33(1): 75-80, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21377962

RESUMO

The mitochondrial cytochrome oxidase I (mtDNA-COI) gene was used to investigate the intraspecific genetic subdivision among 12 geographical populations of Gampsocleis sedakovii distributed in Jilin, Liaoning, Inner Mongolia, Hebei, and Sichuan provinces, China. As for the 626 bp mtDNA-COI sequences of 36 individuals, 29 haplotypes and 71 (11.3%) polymorphic sites were detected, including 37 parsimony informative and 34 singleton variable sites. The results of the analysis of molecular variance (AMOVA) showed that the percentage of variation within populations (37.23%) was less than that among populations. The Fst value was 0.62770 (P< 0.001), and the genetic divergence among populations was significant. Maximum parsimony (MP) analysis revealed two clearly differentiated branch (Ⅰ and Ⅱ) with high bootstrap support (100%). However, these two branches did not correspond in the subspecies distinction based on morphological character. Based on the habitats analysis, we preliminary inferred that morphological divergence between Gampsocleis se-dakovii sedakovii and Gampsocleis sedakovii obscura was the result of habitat dissimilarity. The majority of the G. se-dakovii individuals collected in NTL (Tongliao, Inner Mongolia) were identified as the members of branch Ⅱ, but one individual (NTL-3) belonged to branch Ⅰ. Thus, at least this locality was occupied by two phylogenetically independent individuals. Haplotypes (H10) were shared by three localities, NTL, NEWK (Ewenke, Inner Mongolia) and JJL (Jilin, Jilin), indicated that they shared a common ancestor. We approved that Northeastern China (Manchuria China) was the center of G. sedakovii genetic differentiation, but disapproved the subspecies distinction based on morphological character.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Ortópteros/genética , Animais , China , DNA Mitocondrial/química , DNA Mitocondrial/genética , Ecossistema , Genética Populacional , Haplótipos , Ortópteros/classificação , Filogenia
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